Articulating suturing device and method

ABSTRACT

Devices, systems, and methods for suturing of body lumens allow the suturing of vascular puncture sites located at the distal end of a percutaneous tissue tract. An elongated articulated foot of the device can be inserted through the penetration and actuated so that the foot extends along the lumenal axis. The foot can carry suturing attachment cuffs with one end of the cuff adapted to receive a needle, while the other end receives suture. A portion of the foot and/or lumen of the shaft can receive a portion of the suture and can include friction reducing structure that aid with movement of the sutured during removal of the cuffs from within the penetration.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation application of U.S. patent application Ser. No.12/955,863 filed Nov. 29, 2010, now U.S. Pat. No. 8,252,008, which is acontinuation of U.S. patent application Ser. No. 11/465,527, filed Aug.18, 2006, now U.S. Pat. No. 7,842,048, the disclosure of which are eachincorporated herein by this reference.

This application also relates to U.S. patent application Ser. No.10/357,984, filed Feb. 4, 2003, which is a continuation-in-part of U.S.patent application Ser. No. 10/152,272, filed May 20, 2002, now U.S.Pat. No. 6,984,668, which is a continuation-in-part of U.S. patentapplication Ser. No. 09/651,344, filed Aug. 29, 2000, now U.S. Pat. No.7,001,400, which is a division of U.S. patent application Ser. No.09/262,402, filed on Mar. 4, 1999, now U.S. Pat. No. 6,136,010, thedisclosures of each is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. The Field of the Invention

The present invention relates generally to apparatus and methods for thesuturing of body lumens. More particularly, the present inventionrelates to techniques for percutaneous closure of arterial and venouspuncture sites, which are usually accessed through a tissue tract.

2. The Relevant Technology

A number of diagnostic and interventional vascular procedures are nowperformed translumenally. A catheter is introduced to the vascularsystem at a convenient access location and guided through the vascularsystem to a target location using established techniques. Suchprocedures require vascular access, which is usually established duringthe well-known Seldinger technique, as described, for example, inWilliam Grossman's “Cardiac Catheterization and Angioplasty,” 3^(rd)Ed., Lea and Febiger, Philadelphia, 1986, incorporated herein byreference. Vascular access is generally provided through an introducersheath, which is positioned to extend from outside the patient body intothe vascular lumen.

When vascular access is no longer required, the introducer sheath isremoved and bleeding at the puncture site stopped. One common approachfor providing hemostasis (the cessation of bleeding) is to applyexternal force near and upstream from the puncture site, typically bymanual or “digital” compression. This approach suffers from a number ofdisadvantages. It is time consuming, frequently requiring one-half houror more of compression before hemostasis is assured. Additionally, suchcompression techniques rely on clot formation, which can be delayeduntil anticoagulants used in vascular therapy procedures (such as forheart attacks, stent deployment, non-optical PTCA results, and the like)wear off. This can take two to four hours, thereby increasing the timerequired before completion of the compression technique. The compressionprocedure is further uncomfortable for the patient and frequentlyrequires analgesics to be tolerable. Moreover, the application ofexcessive pressure can at times totally occlude the underlying bloodvessel, resulting in ischemia and/or thrombosis. Following manualcompression, the patient typically remains recumbent from four to asmuch as twelve hours or more under close observation so as to assurecontinued hemostasis. During this time renewed bleeding may occur,resulting in blood loss through the tract, hematoma and/orpseudo-aneurysm formation, as well as arteriovenous fistula formation.These complications may require blood transfusion and/or surgicalintervention.

The incidence of complications from compression-induced hemostasisincreases when the size of the introducer sheath grows larger, and/orwhen the patient is anticoagulated. It is clear that the compressiontechnique for arterial closure can be risky, and is expensive andonerous to the patient. Although the risk of complications can bereduced by using highly trained individuals, dedicating such personnelto this task is both expensive and inefficient. Nonetheless, as thenumber and efficacy of translumenally performed diagnostic andinterventional vascular procedures increases, the number of patientsrequiring effective hemostasis for a vascular puncture continues toincrease.

To overcome the problems associated with manual compression, the use ofbioabsorbable fasteners or sealing bodies to stop bleeding haspreviously been proposed. Generally, these approaches rely on theplacement of a thrombogenic and bioabsorbable material, such ascollagen, at the superficial arterial wall over the puncture site. Whilepotentially effective, this approach suffers from a number of problems.It can be difficult to properly locate the interface of the overlyingtissue and the adventitial surface of the blood vessel. Locating thefastener too far from that interface can result in failure to providehemostasis, and subsequent hematoma and/or pseudo-aneurysm formation.Conversely, if the sealing body intrudes into the arterial lumen,intravascular clots and/or collagen pieces with thrombus attached canform and embolize downstream, causing vascular occlusion. Also, thrombusformation on the surface of a sealing body protruding into the lumen cancause a stenosis, which can obstruct normal blood flow. Other possiblecomplications include infection, as well as adverse reaction to thecollagen or other implant.

A more effective approach for vascular closure has been proposed in U.S.Pat. Nos. 5,417,699, 5,613,974; and PCT published Patent Application No.PCT/US96/10271 filed on Jun. 12, 1996, the full disclosures of which areincorporated herein by reference. A suture-applying device is introducedthrough the tissue tract with a distal end of the device extendingthrough the vascular puncture. One or more needles in the device arethen used to draw suture through the blood vessel wall on opposite sidesof the puncture, and the suture is secured directly over the adventitialsurface of the blood vessel wall to provide highly reliable closure.

While a significant improvement over the use of manual pressure, clamps,and collagen plugs, certain design criteria have been found to bedesirable for successful suturing to achieve vascular closure. Forexample, it is highly beneficial to properly direct the needles throughthe blood vessel wall at a significant distance from the puncture sothat the suture is well anchored in the tissue and can provide tightclosure. It is also highly beneficial to insure that the needledeployment takes place when the device is properly positioned relativeto the vessel wall. The ease of deployment and efficacy of the procedurecan further be enhanced by reducing the cross-section of that portion ofthe device, which is inserted into the tissue tract and/or the vesselitself, which may also allow closure of the vessel in a relatively shortamount of time without imposing excessive injury to the tissue tract orvessel.

For the above reasons, it would be desirable to provide improveddevices, systems, and methods for suturing vascular punctures. The newdevice should have the capability of delivering a pre-tied knot to anincision site. It would be particularly beneficial if these improveddevices provided some or all of the benefits while overcoming one ormore of the disadvantages discussed above.

BRIEF SUMMARY OF THE INVENTION

The present invention provides improved devices, systems, and methodsfor suturing of body lumens. The device often allows the suturing ofvascular puncture sites located at the distal end of a percutaneoustissue tract with greater ease, in less time, and with less patienttrauma than known systems. Vascular puncture site suturing can begenerally provided through the use of shafts having smallercross-sections than prior suturing systems. In the exemplary embodiment,an elongate articulated foot near a distal end of a shaft can beinserted through the penetration and actuated so that the foot extendsalong the lumenal axis. The foot can carry suture attachment cuffs, andcan be drawn proximally up against the endothelial surface of the bloodvessel. Needles can be advanced from the shaft, through the vessel wallbeyond the penetration, and into engagement with the needle cuffs. Thecross-section of the shaft within the tissue tract can be minimized bylaterally deflecting the needles before they leave the shaft, whiletapered depressions within the foot can help guide the advancing needlesinto engagement with the cuffs. The cuffs can lockingly engage theneedles so that the cuffs can be withdrawn proximally along the needlepaths through the tissue tract so as to form a loop of suture across thepuncture without having to thread the needles directly with the sutureinside the blood vessel. The suture loop may be drawn distally from theshaft, proximally from within the blood vessel, or laterally down one ofthe needle paths, across the puncture, and out the opposing path. Theinterior of the shaft can be configured to aid with releasing the sutureloop. More generally, the interior of the shaft can include one or morefriction reducing structures or structures that reduce the frictionalengagement between the portion of the device forming the slot and theflexible filament.

Regardless, the articulating foot may be realigned with the shaft andwithdrawn proximally through the tissue tract in a small profileconfiguration. The use of an articulatable foot in combination withlateral deflection of the needles can avoid dilation of the tissuetract, as was often necessary using known puncture closure systems.

In one configuration, the invention can provide a method for suturing apuncture through a vessel wall of a blood vessel. The puncture can bedisposed within a tissue tract of a patient body, and the method cancomprise attaching a flexible filament to a first fitting. The firstfitting can be inserted through the tissue tract and positioned adjacentthe vessel wall, and a needle path can be formed by advancing a firstneedle through the vessel wall. The needle can be coupled with the firstfitting, and the first needle, the first fitting, and at least a portionof the filament can be withdrawn through the vessel wall along theneedle path.

First and second fittings can often be coupled to the flexible filament,and can generally be positioned so that the puncture can be disposedtherebetween. The flexible filament can often comprise a sutureextending between the first and second fittings, with each fitting beingdrawn proximally by an associated needle so as to form the suture loop.Alternatively, at least one of the needles may include a detachable tipand may advance a suture distally along the needle path as the needlepenetrates through the vessel wall. The flexible filament can againcouple the first and second fittings, here allowing both fittings to bewithdrawn along a single needle path so that the suture advances downalong the first needle path, laterally across the puncture, and then outthe other needle path.

Positioning of the fittings can be generally effected by articulating anelongate foot within the blood vessel so that the foot extends along thevessel axis. A confirmation lumen may extend along a shaft supportingthe foot to ensure that the foot is positioned within the vessel priorto articulation. Once the foot is properly articulated, it can bewithdrawn to firmly engage the endothelial layer of the vessel. The footcan include tapering depressions, which direct the advancing needletoward the fitting, and the suture or other flexible filament adjacentthe fittings can be releasably restrained within a narrow slot extendingfrom the depression. This slot can optionally include one or morefriction reducing structures or structures that reduce the frictionalengagement between the portion of the device forming the slot and theflexible filament.

The suture or other flexible filament and its associated slot can bearranged to avoid entanglement of the advancing needle in the suture,and to ensure that the fitting and suture can be withdrawn proximally asthe needle is retracted. An atraumatic, flexible monorail guidebody mayextend from the shaft and/or the articulatable foot to facilitatealignment of the foot with the vessel, and also to help providehemostasis while the knot is tied. A wide variety of foot articulationmechanisms may be provided, with deployment optionally being effectedwhen the foot is disposed entirely within the vessel and using anactuator and foot motion that avoid dilation of the puncture.

In another configuration, the invention can provide a method forsuturing an opening in a tissue. The method can comprise inserting adistal end of a device through the opening, the device defining a deviceaxis. An elongated foot of the device can be articulated so that firstand second ends of the foot extend laterally with the opening alignedtherebetween. A first needle path can be formed from the device, throughthe tissue, and to the first end of the foot. A second needle path canbe formed from the device, through the tissue, and to the second end ofthe foot. Suture can be advanced along the first and second needle pathsto position a suture loop across the opening.

These and other objects and features of the present invention willbecome more fully apparent from the following description and appendedclaims, or may be learned by the practice of the invention as set forthhereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

To further clarify the above and other advantages and features of thepresent invention, a more particular description of the invention willbe rendered by reference to specific embodiments thereof which areillustrated in the appended drawings. It is appreciated that thesedrawings depict only typical embodiments of the invention and aretherefore not to be considered limiting of its scope. The invention willbe described and explained with additional specificity and detailthrough the use of the accompanying drawings in which:

FIG. 1 illustrates a perspective view of a percutaneous blood vesselclosure device according the principles of the present invention.

FIG. 2 illustrates the vessel closure device of FIG. 1 in which anelongate foot is shown in a deployed position.

FIGS. 2A-C illustrate actuation of a foot and advancement of needlesfrom a shaft to the articulated foot in a device similar to the deviceof FIG. 1.

FIG. 3A is a detailed view showing the foot of the vessel closure deviceof FIG. 1 in a parked position prior to deployment.

FIG. 3B is a detailed view showing the foot of the vessel closure deviceof FIG. 1 in a deployed position.

FIGS. 4 and 4A are perspective views illustrating a suture attachmentcuff and an associated barbed needle for use in the vessel closuredevice of FIG. 1.

FIG. 5 is a cross-sectional view showing the barbed needles securinglyengaging the suture cuffs of the deployed foot.

FIGS. 6A-C illustrate one embodiment of a deployable foot, in which thefoot slides and pivots when drawn proximally by a tension member.

FIG. 7A-B illustrate the suture cuff positioned within a needlereceptacle, the suture being releasably secured within a slot extendingradially from the needle receptacle, and friction reducing structuresformed in the slot.

FIGS. 8A-C illustrate an alternative foot articulation mechanism inwhich lateral slots on the foot receive pins from the shaft to allow thefoot to pivot and slide axially.

FIGS. 9A and B illustrate a still further alternative foot actuationmechanism in which the foot slides axially within a slot.

FIGS. 9C and D illustrate a further foot actuation mechanism in whichrelative movement between the sides of a two-part shaft actuates thefoot.

FIGS. 10A-D illustrate alternative structures and techniques foravoiding entanglement of the needle with the suture.

FIGS. 11A-E illustrate an alternative closure system and method for itsuse in which a first needle advances the suture to the foot, while asecond needle engages and withdraws both the first and second suturecuffs, a flexible filament connecting the suture cuffs, and at least aportion of the suture from within the blood vessel so as to complete apre-tied knot.

FIGS. 12A and B illustrate an alternative device having two pairs ofneedles and a foot with four needle receptacles so as to form two loopsof suture across a puncture of a blood vessel.

FIGS. 13A-H illustrate a method for use of a suture system so as toeffect hemostasis of a blood vessel puncture through a tissue tract.

FIGS. 14A and 14B are enlarged partial side views of a suturing devicein accordance with one embodiment of the present invention.

FIGS. 15A through 15F are enlarged cross-sectional views of theembodiment of the suturing device of FIGS. 14A and 14B.

FIGS. 16A and 16B are schematic views of a suture bight having apre-tied knot in accordance with one embodiment of the presentinvention.

FIGS. 17A through 17E show enlarged partial cross-sectional views of anembodiment of the suturing device in accordance with the invention, inwhich one embodiment of a penetrator tip and cuff engagement, penetratortip disengagement, and cuff ejection sequence is illustrated.

FIG. 18A is an enlarged partial cross-sectional view of an embodiment ofa foot in accordance with the present invention, showing the linkrouting through the suture bearing surfaces of the foot.

FIG. 18B is an enlarged partial cross-sectional view of an embodiment ofa device in accordance with the present invention, showing the linkrouting through a suture-bearing surface located distal to the foot.

FIGS. 19A and 19B are enlarged partial cross-sectional views of anembodiment of a foot in accordance with the present invention, showingan alternate penetrator tip and cuff engagement, penetrator tipdisengagement, and cuff ejection sequence.

FIGS. 20A through 20C are enlarged partial cross-sectional views of anembodiment of a foot in accordance with the present invention, showingan alternate penetrator tip and cuff engagement, penetrator tipdisengagement, and cuff ejection sequence.

FIG. 21A is an enlarged perspective view of an embodiment of thepre-tied knot in accordance with the present invention.

FIG. 21B is a cross-sectional view of a suture storage tube according toan alternate configuration of the device of FIG. 21A.

FIGS. 22A through 22C show an alternate embodiment of a foot inaccordance with the invention.

FIGS. 23A through 23C show another alternate embodiment of a foot inaccordance with the invention.

FIGS. 24A and 24B are perspective views of an alternative embodiment ofa penetrator tip in accordance with the invention.

FIGS. 25A through 25C are schematic views of an alternate embodiment ofa vessel closure device in accordance with the present invention.

FIGS. 26A through 26D are schematic views of alternate embodiments of avessel closure device in accordance with the invention.

FIG. 27 shows a schematic view of one embodiment of a link and cuffassembly in accordance with the invention.

FIG. 28 shows a bight of suture wrapped on a mandrel to form a pre-tiedknot in accordance with the invention.

DETAILED DESCRIPTION

A suturing device, which delivers a pre-tied knot to an incision, isdisclosed. As an overview, a suturing device in accordance with thepresent invention includes a first penetrator having a pre-tied knotdisposed thereabout and a second penetrator having suture disposedthereon. During operation of the suturing device, the first penetratorand the second penetrator penetrate the tissue about a periphery of anincision in a body lumen. Upon penetration, a penetrator tip releasablyengaged with the first penetrator couples with a foot of the suturingdevice. As the first and second penetrators retract from the body lumen,the penetrator tip and the suture coupled with the penetrator tipretract through a penetration formed in the body lumen by the firstpenetrator. As will be discussed in greater detail with reference to theaccompanying Figures, as the suture retracts, the pre-tied knot receivesthe suture, forming a knot for suturing the incision in the body lumen.

Referring now to FIG. 1, a vessel closure device 10 generally has ashaft 12 having a proximal end 14 and a distal end 16. A proximalhousing 18 supports a needle actuation handle 20. A flexible, atraumaticmonorail guidebody 22 extends distally of distal end 16 of shaft 12.

As can be seen with reference to FIG. 2, a foot 24 is articulatablymounted near the distal end of shaft 12. Foot 24 moves between a lowprofile configuration, in which the foot is substantially aligned alongan axis of shaft 12 (as illustrated in FIG. 1), to a deployed position,in which the foot extends laterally from the shaft, upon actuation of afoot actuation handle 26 disposed on proximal housing 18.

FIGS. 2A through C illustrate the structure and actuation of foot 24 ofa device 10′ having a modified proximal housing, and also show howneedles 38 can be advanced distally from shaft 12 to the foot bydepressing needle actuation handle 20. It will be understood that thediscussion made with respect to device 10 can also apply to device 10′and other devices described herein, and vice versa.

Actuation of foot 24 is illustrated more clearly in FIGS. 3A and B. Inthe parked position illustrated in FIG. 3A, foot 24 extendssubstantially along axis 28 of shaft 12. Note that the axis of the shaftneed not be straight, as the shaft may curve somewhat, particularlyadjacent the foot. In the exemplary embodiment, foot 24 is substantiallydisposed within a foot receptacle 30 of shaft 12 so as to minimize thecross-section of the device adjacent the foot prior to deployment.Advantageously, prior to deployment of the foot, device 10 can have across-section adjacent foot 24 of about 7 Fr or less, ideally having across-section of about 6 Fr or less for the entire device distally ofthe proximal end 14 of shaft 12.

Actuation of foot handle 26 slides a foot actuation wire 32 proximally,pulling foot 24 from a parked position to the deployed positionillustrated in FIG. 3B. Once deployed, a first end 24 a and a second end24 b of foot 24 extend laterally from the shaft. Suture 34 herecomprises a continuous filament with ends disposed in needle receptaclesadjacent each end of the foot. An intermediate portion of suture 34 mayextend proximally along a suture lumen of shaft 12 to and/or beyondproximal housing 18. Alternatively, in device 10, the length of suturebetween the ends may extend distally within flexible guidebody 22 in adedicated lumen (separate from the monorail guidewire lumen). In stillfurther alternatives described below, a short length of suture or someother flexible filament may extend substantially directly between theneedle receptacles. Addition information regarding the suture lumen orsuture storage structure is provided hereinafter.

Shaft 12 also includes a foot position verification lumen that extendsdistally from a position verification port 36 to a position indicator athousing 18. When the foot is properly positioned within the bloodvessel, blood pressure will cause blood to flow proximally through theindicator lumen to the indicator. The indicator may optionally comprisea blood exit port, a clear receptacle in which blood is visible, or thelike. In the exemplary embodiment, the indicator of handle 18 comprisesa length of clear tubing extending from housing 18 (not shown) in whichthe blood is clearly visible. It should be understood that a widevariety of alternative position verifications sensors might be used,including electrical pressure sensors, electrolytic fluid detectors, orthe like.

The structures used in positioning a loop of suture across the puncturecan be understood with reference to FIGS. 4, 4A, and 5. In generalterms, needles 38 extend from shaft 12 into secured engagement withfittings 40 attached to sutures 34. More specifically, needles 38include a barbed end 42 defining a recessed engagement surface 44.Fittings 40 are roughly cylindrical structures having an axial channel46 that receives barbed end 44 of needle 38 therein. A first slot is cutin fitting 44 so as to define at least one tab 48. Tabs 48 can beresiliently biased inward into channel 46. As needle 38 advances intofitting 40, barbed end 42 resiliently displaces tab 48 clear of channel46 so as to allow the barbed end to pass axially into the fitting. Oncebarbed end 42 is disposed axially beyond tab 48, the tab 48 resilientlyflexes back into the channel, capturing needle 38 by engagement betweenthe tab 48 and recessed surface 44. As each tab 48 can hold the fitting40 in place on the needle 38, the use of more than one tab increases thereliability of the system. Ideally, three tabs are provided, asillustrated in FIG. 4A.

To facilitate attachment of fitting 40 to suture 34, a second slot cutin the tubular fitting structure defines a suture attachment collar 50.Optionally, collar 50 may be crimped about suture 34 to mechanicallyaffix the suture to fitting 40. In addition and/or instead of mechanicalcrimping, suture 34 may be bonded to fitting 40 using an adhesive, heat,fasteners, knots, or the like.

Fitting 40 is quite small in size, and is generally configured tofacilitate withdrawing the fitting (and the attached suture) along withneedle 38 axially through the vessel wall along the needle path. Needle38 can generally have a cross-sectional width of between about 0.010inches and 0.020 inches. Barb 42 can extend laterally so as to define anengagement surface 44 having a protruding length of between about 0.002inches and 0.005 inches. Fitting 40 can have a cross-sectional sizeroughly corresponding to or only slightly larger than needle 38. Fitting40 can have an outer lateral width of between about 0.014 inches and0.025 inches, and an axial length of between about 0.035 inches and0.050 inches. Channel 46 can be sized to receive at least a portion ofneedle 38, and can generally have a width of between about 0.010 inchesand 0.020 inches. Suture 34 can extend axially opposite the open end ofchannel 46 so as to minimize drag when the suture is drawn proximallyalong the needle path. In the exemplary embodiment, needle 38 has adiameter of about 0.020 inches, while the fitting comprises a tubehaving an outer diameter of about 0.020 inches, an inner diameter ofabout 0.016 inches, and an overall length of about 0.047 inches. Thefitting can comprise a resilient material, optionally comprising ametal, and in the exemplary embodiment, comprising stainless steel.

Needles 38 typically have a length of between about 5.0 inches and 6.0inches, and can be sufficiently stiff to be advanced in compressionthrough the vessel wall (and adjacent tissues) for up to 0.5 inches whensupported in cantilever. Nonetheless, the needles can be flexible enoughto be laterally deflected within shaft 12, as can be understood withreference to FIG. 5. Needles 38 generally comprise a high strengthmetal. In one configuration, the high strength metal comprises stainlesssteel, although various other metals are possible. Fittings 40 can alsocomprise a flexible material to allow tab 48 to flex out of the way ofbarbed end 42, and to resiliently rebound and engage recessed surface44. In the exemplary embodiment, barbed end 42 has a diameter of about0.015 inches, with the diameter of the needle decreasing to about 0.008inches proximally of the barb so as to define the recessed engagementsurface.

As was generally described above, foot 24 includes needle receptacles 52adjacent the ends of the foot. A fitting 40 (with an associated end ofsuture 34) is disposed within each needle receptacle and a surface ofthe receptacle tapers proximally and outwardly so as to guide theadvancing needles 38 into engagement with fittings 40 when foot 24 is inthe deployed position. As fittings 40 (and associated portions of suture34) are releasably supported in the foot, needles 38 can be withdrawnproximally so as to draw the fittings and suture ends from the footproximally into (and optionally through) shaft 12. The needlereceptacles of the exemplary embodiment taper outward at an anglebetween 20 and 35 degrees from the centerline of fitting 40, and thefitting is held in a recess having a diameter of about 0.0230 inches anda length of about 0.042 inches. A lateral opening or window through theside of foot to the fitting recess may be provided to facilitate needleand/or cuff positioning during assembly of the device, and a protrudingcollar near the proximal end of the fitting recess may help keep thefitting in position.

FIG. 5 also illustrates the lateral deflection of needles 38 by needleguides 54 of shaft 12. This lateral deflection of the needles allows theuse of a small diameter shaft, while still encompassing sufficienttissue within the suture loop on opposite sides of the puncture so as toeffect hemostasis when the suture looped is tightened and secured. Inthe exemplary embodiment, shaft 12 comprises an outer casing of abiocompatible material such as stainless steel, carbon fiber, nylon,another suitable polymer, or the like. Needle guides 54 may be definedat least in part as lumens formed within the casing of a polymericmaterial such as nylon or the like. In some embodiments, shaft 12 maycomprise a carbon fiber filled nylon, or carbon fiber filled with analternative material.

One example of a suitable structure and articulation motion for foot 24is illustrated in FIGS. 6A and B. Foot actuation wire 32 (see FIG. 3A)rides in a lumen of shaft 12, and draws foot 24 from a parked position(shown in FIG. 6A) to a deployed position (shown in FIG. 6B) through acombination of sliding and pivoting of the foot. The foot remainssupported throughout its range of motion by arms disposed laterally oneither side of the foot, the arms defining (at least in part) footreceptacle 30. Once foot 24 is deployed, needle receptacles 52 and/orthe fittings disposed therein can define a lateral suturing width 56 ina range from about 0.260 inches to about 0.300 inches. Foot 24 may bemachined or cast from a polymer or metal, but can comprise a polymersuch as carbon fiber filled nylon. In some cases, foot 24 may be moldedas two separate halves that can subsequently be affixed together.Needles 38 advance from the fixed needle guides 54, and are laterallydirected into fittings 40 by receptacles 52, as illustrated in FIG. 6C.In general, a shape memory alloy such as Nitinol® in its superelasticregime provides a particularly advantageous actuator wire formanipulating foot 24.

Referring now to FIG. 7A, fittings 40 and suture 34 can be withdrawnproximally by the needles from needle receptacles 52. To releasablysupport fittings 40 and suture 34 and avoid entanglement of the suturein the needles, suture 34 is fittingly received within a slot 58 thatextends laterally from needle receptacles 52. As the needles pull thefitting axially from needle receptacles 52, suture 34 is pulled fromslot 58 and free from foot 24. Bending of the suture proximally withinthe suture slot 58 can also locally increase the suture width, so thatthe interaction between the bent suture and the slot can help hold thefitting in the recess.

The suture slot 58, or a portion thereof, can be configured to reducethe frictional engagement or contact between the suture and the foot 24.For example, and with reference to FIG. 7B, a portion of the slot 58 caninclude an interior surface 84 with friction reducing structures. Theillustrated interior surface 84 can include at least one raised portion86 and at least one recessed portion 88, optionally a plurality ofraised portions 86 and a plurality of recessed portions 88, which extendlongitudinally along the length of the slot 58. The combination of theraised portions 86 and recessed portions 88 reduces the contact surfacebetween the suture 43 (FIG. 7A) and the slot 58 and thereby reduce thefrictional forces between the suture 34 and the slot 58 or reduces thesuture drag when the suture is moved inside the slot 58. The portions 86and 88 are one example of a structure capable of performing the functionof reducing frictional engagement between a suture and the structurewhich selectively receives and/or restrains the suture. Other structurescan perform this desired function. For instance, and not by way oflimitation, the interior surface can include one or more spaced apartraised portion, without recessed portions. For instance, the interiorsurface can include one or more protrusions that function or act asraised portions. In another configuration, instead of extendinglongitudinally along the length of the slot or other structure whichselectively receives and/or restrains the suture, the structure capableof performing the function of reducing frictional engagement can be (i)helically formed in the interior surface, (ii) formed at some otherangular orientation relative to the longitudinal axis of the structurethat selectively receives and/or restrains the suture, (iii) formed froma plurality of individual raised and/or recessed portions distributedupon the interior surface, either uniformly or non-uniformly, and/or(iv) combinations of the same.

As illustrated, the raised portions 86 define a first inner diameterid₁, while the recessed portions 88 define a second inner diameter id₂.In the illustrated configuration, the id₁ can be about 0.030 inches,while id₂ can any diameter greater than the id₁, for instance about0.040 inches. It will be understood by those skilled in the art thatvarious other configurations are possible. For example, although theraised portions 86 and the recessed portions 88 are generally uniformlydistributed on the interior surface 84 in an alternating fashion,irregular distribution of the portions 86 and 88 is possible. Further,although the portions 86 and 88 are generally depicted as being uniformin size, shape, or general configuration, non-uniform size, shape, orconfiguration of portions 86 and 88 are possible. In addition, the id₁and id₂ can be any desired diameter greater or lesser than thoseidentified herein. For instance, and not by way of limitation, id₁ canbe greater or lesser than 0.030 inches, while id₂ can be greater orlesser than 0.040 inches, so long as id₂ is greater than id₁.

While the above discussion regarding structures to reduce frictionalcontact is directed to reducing frictional contact between the suturesand the slot of the foot, it will be understood by those skilled in theart that structure similar to those described herein can be used in anyportion of the device that may obtain a benefit from reducing thefrictional contact with the suture. For instance, and not by way oflimitation, portions of the shaft or lumen of the shaft, tubular membersdisposed within a lumen of the shaft or integrally formed with theshaft, the handle, the guidebody, the foot, or any other portion of thedevice, or other devices described herein may also include lumens orslots that include friction reducing structures.

A wide variety of foot actuation mechanisms might be used within thescope of the present invention. A first alternative foot actuationarrangement is illustrated in FIGS. 8A-C. In this embodiment, a shaft 12i has pins 60 which ride in associated slots 62 of a foot 24 i. Proximalmotion of an actuation wire causes foot 24 i to move axially androtationally, with pins 60 sliding along slot 62, and the foot pivotingabout the pins. In this embodiment, guidebody 22 extends directly fromthe foot, as illustrated in FIG. 8C.

A still further alternative foot actuation mechanism is illustrated inFIGS. 9A and B. In this embodiment, slidable foot 24 ii is glidinglyreceived within a receptacle 30 of shaft 12 ii. Sliding of the foot 24ii from the parked position of FIG. 9A to the deployed position of FIG.9B places the needle receptacles 52 in the paths of needles from theshaft 12 ii without pivoting of the foot. Guidebody 22 (see FIG. 1) canextend here from a distal end of shaft 12 ii at a fixed angle from theshaft. Optionally, insertion through the tissue tract may be facilitatedby including an additional bend in the shaft axis adjacent the guidebodyon many embodiments.

Yet another foot actuation mechanism can be understood with reference toFIGS. 9C and D. Shaft 12 iii is formed in two parts, which slide axiallyrelative to each other when foot actuation lever 26 iii moves, using anoffset crank arrangement. A similar offset crank supports foot 24 iii,so that the sliding shaft parts cause the foot to pivot as shown.

A variety of features may be included in the articulatable foot, theneedle receptacle, and/or the needle to avoid tangling of the needle inthe suture as the needle is directed to the fitting. As illustrated inFIG. 10A, a moveable flap 64 may extend over slot 58 so that theadvancing needle slides along the flap toward the fitting, rather thanentering the slot and engaging the suture directly. Flap 64 may beaffixed along one side of the slot, with the other side of the flapflexing into the receptacle to release the suture from slot 58 when thefitting and suture are withdrawn by the needle.

An alternative mechanism for avoiding entanglement of the needle withthe suture is illustrated in FIG. 10B. In this embodiment, needlereceptacles 52 i have tangential slots 58 i which extends substantiallytangentially to the surface of the receptacle. As a result of thistangential arrangement, a needle entering the receptacle 52 i will bedirected toward the fitting contained therein, but will generally not beable to enter and advance within the tangential slot 58 i so as tobecome entangled with the suture. As illustrated in this embodiment, theslots may optionally extend laterally through the foot so that the loopof suture can be pulled from one side of the shaft without interference.Interference can also be prevent or substantially reduced by formingfriction reducing structures within the interior of the shaft. Thesefriction reducing structures can be similar to those described withrespect to FIGS. 7A and 7B.

A still further alternative mechanism for avoiding entanglement betweenthe suture and the needle is illustrated in FIGS. 10C and D. Two-partneedle 38 i includes an outer sheath 66 and an inner core 68. The partsof these needles initially advance together into the receptacles withthe needle core 68 withdrawn so that the needle presents a smoothtapered tip (the combined tip preferably being larger in diameter thanthe slot containing the suture) as illustrated in FIG. 10C. Oncetwo-part needle 38 i is fully positioned within the needle receptacle,needle core 68 may extend axially to expose barbed tip 42 and recessedengagement surface 44 and to secure the needle to the fitting within theneedle receptacle. In the exemplary embodiment of FIGS. 4 and 5, barbedtip 42 is formed integrally with the rest of the needle structure, butthe tip has a larger cross-section than radial slot 58 containing thesuture 34. As a result, the barbed tip is unable to enter the slot,thereby avoiding entanglement between the needle and suture.

An alternative vessel closure device 70 will be explained with referenceto FIGS. 11A through 11E. This embodiment includes an articulatable foot24 having a pair of needle receptacles 52, as described above. Althougheach needle receptacle 52 contains a fitting 40 for coupling a flexiblefilament to a tip of an associated needle, the filament in this casecomprises a short length of suture 74 (or some temporary connectingfilament, as shown schematically in phantom in FIG. 11A) spanningdirectly between the needle receptacles. Rather than pulling the twoends of an extended loop through the needle paths and proximally out thetissue tract for tying, closure system 70 advances a single end of thesuture distally along one needle path, across the puncture, and thenproximally along the other needle path. To provide this interaction, atleast one needle includes means for attaching suture 34 to short suture74, here in the form of a detachable coupling structure carried on theat least one needle. This structure facilitates the use of a pre-tiedknot.

Referring now to FIGS. 11A and B, the distal end of device 70 advancesdistally through skin S and into a tissue T of the patient while thedevice is in the small profile configuration with foot 24 aligned alongthe axis of the device. Here, however, an end 76 of suture 34 is affixedto a detachable needle tip 78 of a hollow needle 38′. Detachable tip 78comprises a fitting having an opening receiving an end of suture similarto fitting 40, attached to a barbed needle end (similar to that ofneedle 38). Suture 34 may extend proximally within hollow needle 38′where the needle has an open channel along its length, may exit thehollow needle 38′ just proximally of detachable tip 78, or may bedisposed alongside a solid needle. Needle 38 (opposite hollow needle38′) has a fixed barbed tip, as described above, and a bight of suture80 is releasably attached to the device shaft encircling the opening ofneedle guide 54 of the fixed tip needle 38. The bight of suture may bereleasably disposed within a slot of the device, may be temporarily heldin place by a weak adhesive or coating, or the like. A second end 82 ofsuture 34 extends proximally along the shaft of the device, the secondend of the suture optionally also being releasably held along the shaft.

Bight 80 can define a knot when first end suture passes therethrough, ascan be understood with reference to FIGS. 11Ai and 11Aii. Bight 80 canoften include more than one loop, and may be pre-arranged so as todefine a square knot (using the layout schematically illustrated in FIG.11Ai), a clinch knot (FIG. 11Aii), or a variety of known or new surgicalknots.

Device 70 advances along tissue tract TT to puncture P in blood vesselV. Once foot 24 is disposed within a blood vessel V, a pull wire movesthe foot proximally and pivots the foot laterally so that the footextends along an axis A of the vessel, as illustrated in FIG. 11B. Thefoot can then be pulled proximally against an inner surface of thevessel wall W to ensure that the needle receptacles 52 are properlypositioned.

As can be understood with reference to FIGS. 11C and D, hollow needle38′ and needle 38 advance to engage fittings 40 within receptacles 52.Hollow needle 38′ draws first end 76 of suture 34 distally throughvessel wall W, and detachable tip 78 is secured into an associatedfitting 40 using the barb and tab interaction described above. As shortsuture 74 extends between fittings 40, and as detachable tip 78 can pullfree of hollow needle 38′ when the needles are withdrawn, thiseffectively couples needle 38 to first end 76 of suture 34. Thedetachable tip riding partially within the hollow needle (or vice versa)so that the assembly remains together under compression. Hence, needle38 can pull the suture distally along the needle path formed by hollowneedle 38′, across the puncture P, and proximally along the needle pathformed by needle 38, as illustrated in FIG. 11D.

FIGS. 11D and E show that the knot can be completed by pulling needle38, short suture 74, and second end 76 of suture 34 (together with thefittings 40 and detachable needle tip 78) proximally through bight 80.Second end 82 of suture 34 can be pulled to free bight 80, and the endsof the suture can be tightened and the device removed to providepermanent hemostasis.

It will be recognized that removal of device 70 can be facilitated bycoupling first end 76 to bight 80 over an outer surface of the device,and by arranging suture 34 and hollow needle 38′ so that the suture canpull free of the needle when detachable tip 78 is released, for example,by having the suture exit the needle proximally of the tip through achannel that extends to the tip so that the needle does not encircle thesuture. By including such provisions, after foot 24 is returned to thenarrow configuration, the device can be pulled proximally from thetissue tract leaving the pre-tied knot in place.

Alternative arrangements (using the detachable needle ends of device 70)are possible to provide the benefit of a pre-tied knot and the like forclosure of a vessel puncture. For example, a device having a pair ofneedles in which each needle included a detachable tip might be used topull first end 76 through a bight, so that the bight need not encirclethe needle path of one of the needles.

It will be understood that hollow needle 38′ can be modified to aid withthe slidable engagement of the suture with the interior of the lumen ofthe hollow needle 38′. For instance, and not by way of limitation, thelumen of hollow need 38′, or other portion of the suture path, caninclude friction reducing structures as described in FIGS. 7A and 7B.The hollow needle lumen, therefore, can include one or more raisedportions and/or one or more recessed portions that reduce the contactsurface between the suture and the wall or surface of the lumen, slot,or other structure receiving the suture.

In some cases, particularly for closure of large punctures, it may beadvantageous to provide multiple suture loops across the puncture,either in parallel, in an “X” pattern, or the like. As illustrated inFIGS. 12A and B, the present invention encompasses the use of more thantwo needles and associated receptacles, fittings, sutures, and the like.Multiple loop systems may have four, six, eight, or more needles, or mayeven have odd numbers of needles and fittings, particularly where one ormore fittings have a plurality of suture ends extending therefrom. Thisallows a wide variety of stitching patterns to be provided by suchmultiple loop devices.

The method of use of the devices of FIGS. 1-7 can be understood withreference to FIGS. 13A-G. After accessing a blood vessel V (often usingthe Seldinger technique), a guidewire GW is left extending into skin Sand down through tissue T along tissue tract TT. Guidewire GW entersvessel V through a puncture P in vessel wall W, and extends along thevessel throughout many endovascular procedures. As illustrated in FIG.13A, distal guidebody 22 is advanced over the guidewire GW in a monorailfashion, so that the guidewire helps to direct the device along thetissue tract TT and into the vessel through puncture P. FIG. 13B showsthat when sensor 36 is disposed within the vessel, blood can flow fromthe sensor port and through a lumen in shaft 12 to the proximal handleto notify the operator that foot 24 has been advanced far enough fordeployment.

Deployment of the foot is effected by actuation of the foot deploymenthandle, as described and illustrated above with reference to FIGS. 2 and2B. As described above, guidebody 22 helps to align the device with theaxis of vessel V. Guidebody 22 may be set at an angle and/or offsetrelative to shaft 12 as appropriate to aid in alignment with aparticular vessel access technique. As shown in FIG. 13C, the deployedfoot 24 extends laterally from the shaft, so that foot 24 adjacentreceptacles 52 can be drawn up against vessel wall W by gently pullingshaft 12. Hence, the foot helps to accurately position the needle guides54 at a distance from the vessel wall.

Referring now to FIG. 13D, flexible needles 38 are deflected laterallyby needle guides 54 toward receptacles 52 of the deployed foot. As aresult, the needles advance in cantilever both distally and laterallywhen needle actuation handle 20 is pressed (see FIG. 2C), and thetapering surfaces of receptacles 52 help to push the needles back intoalignment with the fittings so as to overcome any unintended deflectionof the needles by tissue T or vessel wall W. This ensures that needles38 securingly engage fittings 40 within receptacles 52, thereby couplingthe ends of suture 34 to the needles. While suture 34 is hereillustrated running along the side of shaft 12 outside foot receptacle30 to a lumen within guidebody 22, it should be understood that thesuture loop might instead extend proximally in a lumen of shaft 12,might be routed through the foot and/or foot receptacle, and/or might bestored in a spool adjacent foot 24. Regardless, suture 34 should able topull free of the device between its ends to form a continuous loopacross puncture P.

To facilitate easy removal from within the guidebody 22 or a lumen ofthe shaft 12, friction reducing structures can be formed withinguidebody 22 or the lumen of shaft 12. Exemplary structures areillustrated in FIG. 13E. As illustrated, a portion of the lumen 58′ ofguidebody 22 can include an interior surface 84′ with friction reducingstructures. The illustrated interior surface 84′ can include at leastone raised portion 86′ and at least one recessed portion 88′, optionallya plurality of raised portions 86′ and a plurality of recessed portions88′, which extend longitudinally along the length of the lumen 58′. Thecombination of the raised portions 86′ and recessed portions 88′ reducesthe contact surface between the suture 34 and the lumen 58′ and therebyreduce the frictional forces between the suture 34 and the lumen 58′ orreduces the suture drag when the suture is moved inside the lumen 58′.The portions 86′ and 88′ are one example of a structure capable ofperforming the function of reducing frictional engagement between asuture and the structure which selectively receives and/or restrains thesuture. Other structures can perform this desired function. Forinstance, and not by way of limitation, the interior surface can includeone or more spaced apart raised portion, without recessed portions. Forinstance, the interior surface can include one or more protrusions thatfunction or act as raised portions. In another configuration, instead ofextending longitudinally along the length of the lumen or otherstructure which selectively receives and/or restrains the suture, thestructure capable of performing the function of reducing frictionalengagement can be (i) helically formed in the interior surface, (ii)formed at some other angular orientation relative to the longitudinalaxis of the structure that selectively receives and/or restrains thesuture, (iii) formed from a plurality of individual raised and/orrecessed portions distributed upon the interior surface, eitheruniformly or non-uniformly, and/or (iv) combinations of the same.

It will be understood by those skilled in the art that various otherconfigurations of the friction reducing structures are possible. Forexample, although the raised portions 86′ and the recessed portions 88′are generally uniformly distributed on the interior surface 84′ in analternating fashion, irregular distribution of the portions 86′ and 88′is possible. Further, although the portions 86′ and 88′ are generallydepicted as being uniform in size, shape, or general configuration,non-uniform size, shape, or configuration of portions 86′ and 88′ arepossible.

While the above discussion regarding structures to reduce frictionalcontact is directed to reducing frictional contact between the suturesand the slot of the foot, it will be understood by those skilled in theart that structure similar to those described herein can be used in anyportion of the device that may obtain a benefit from reducing thefrictional contact with the suture. For instance, and not by way oflimitation, portions of the shaft or lumen of the shaft, tubular membersdisposed within a lumen of the shaft or integrally formed with theshaft, the handle, the guidebody, the foot, or any other portion of thedevice, or other devices described herein may also include lumens orslots that include friction reducing structures.

Referring now to FIGS. 13F and G, fittings 40 and the ends of suture 34are drawn proximally through the vessel wall W along the needle pathsformed by needles 38. Optionally, the needles may be withdrawnproximally out of the tissue tract and clear of shaft 12, or they mayremain coupled to the shaft within needle guides 54. The foot actuatoris moved to store foot 24 along shaft 12, and the shaft can then bepulled proximally from the tissue tract. Guidebody 22, which maycomprise a soft, compliant polymer, may temporarily extend at leastpartially into tissue tract TT and through puncture P to help reduce theloss of blood until the loop is secured.

Now referring to FIG. 13H, once shaft 12 has been withdrawn sufficientlyto expose needle guides 54, the ends of the suture loop can be graspedby the operator. Tying of a knot in suture 34 can then proceed in aconventional manner. The use of a clinch knot may facilitate gradualtightening of the knot while removing guidebody 22, although a widevariety of knot and knot advancing techniques might be used.

FIGS. 14A and 14B show an embodiment of a vessel closure device 100. Thediscussion of vessel closure device 10, 10′, and 70 also can apply tovessel closure device 100, and vice versa. This embodiment includes anarticulatable foot 114 (FIG. 14B) having a pair of penetratorreceptacles (described below). Although each penetrator receptaclecontains a fitting (or cuff) for coupling a flexible filament to a tipof an associated penetrator, the filament in this case may be a shortlength of suture such as a link 112 spanning directly between thepenetrator receptacles. Rather than pulling the two ends of an extendedloop through the needle paths and proximally out the tissue tract fortying, closure system 100 advances a single end of the suture distallyalong one needle path, across the puncture, and then proximally alongthe other needle path. To provide this interaction, at least one needleincludes means for attaching suture 102 to the link 112, here in theform of a detachable coupling structure carried on the at least oneneedle. This structure facilitates the use of a pre-tied knot. It willbe understood that all or portions of the needle path can include one ormore of the friction reducing structures described herein or thosestructures known to one skilled in the art for performing the functionsidentified with the described friction reducing structures.

FIG. 15A shows a side, cross-sectional view of the device 100 in aposition prior to deployment of the foot 114. The device 100 has beenadvanced through the incision 105 in the arterial wall W. For ease ofdescription, reference numeral 122 indicates the anterior side of thedevice, and reference numeral 124 denotes the posterior side of thedevice. Device 100 has a rigid shaft 118 that has channels definedtherein to carry the elongate bodies or penetrators 106 and 106′.Penetrator 106′ may also be referred to as the anterior penetrator, andpenetrator 106 may be referred to as the posterior penetrator. Forpurposed of description and not limitation, the anterior penetrator 106′carries the pre-tied knot 104, and posterior penetrator 106 carries thedetachable coupling structure or penetrator tip 108. Anterior penetrator106′ defines a penetrator tip 108′ at its distal end.

The articulatable foot 114 includes anterior and posterior penetratorreceptacles 116′ and 116, respectively. These receptacles are alsoreferred to as cuff pockets. Cuffs 110 are shown positioned in cuffpockets 116′ and 116. A link 112 extends between the cuffs 110.

FIG. 15B shows the foot 114 deployed so as to position the cuff pockets116 to receive the first and second penetrators 106′ and 106. As shownin FIG. 15B, the anterior penetrator 106′ has the pre-tied knot 104disposed about a proximal portion of its length. Alternatively, thepre-tied knot 104 may be disposed about the periphery of a knot tube,through which the anterior penetrator 106′ may pass (as described infurther detail below).

FIG. 15B illustrates the suturing device 100 deployed within a lumen 107in accordance with an embodiment of the present invention. As may beseen with reference to the Figure, the suturing device 100 includes anelongate body 106′ having a penetrator tip 108′. The elongate bodies 106and 106′ deploy to form penetrations 109 and 109′ within the vessel wallW. The configuration of the penetrator tip 308 allows penetration of thevessel wall W immediately surrounding the incision 105 to form thepenetration 309. As such, the penetration of the penetrator tip 108through the tissue wall W allows for passage of the elongate body 106through the tissue and into the lumen 107. The elongate body 106 holdsthe suture 102 as the elongate body 106 passes through the tissue wall Wimmediately adjacent the incision 105 and into the foot 114.

As may be seen with reference to FIG. 15B, in this embodiment, the foot114 has a single unit design where the cuffs 110 and 110′ are disposedon opposite sides of the suturing device 100 and the foot 114. Thisorientation allows balance of forces during the deployment of theelongate bodies 106 and 106′, thereby allowing precise suturing andminimizing the possibility of incorrectly suturing the incision 105.Also, as may be seen with reference to the Figure, the suturing device100 delivers the suture longitudinally relative to the lumen 107,thereby minimizing arterial diameter constriction. Likewise, in thisembodiment, the foot 114 is positioned at an angle “Q” relative to theshaft 118 of the suturing device 100. In one configuration, the angle“Q” is in a range between about 20 degrees and about 60 degrees, whilein another configuration the angle “Q” is about 40 degrees. The angle“Q” approximates the puncture angle commonly used to access the femoralartery. The angle Q and the rigid character of the shaft 118 serve toprovide accurate, virtually simultaneous “cuff capture” by both theanterior and posterior penetrators. Moreover, since the device 100 canbe used without an introducer sheath, the rigid nature of the shaft 118provides the control of the travel of penetrators as they move distallyto engage the cuffs. The device 100 can therefore be used in the samefemoral artery access puncture without disturbing the existing tissuetract and causing undue discomfort to the patient.

When both the elongate bodies 106 and 106′ and the suture 102 passthrough the lumen wall W and into the lumen 107, the elongate bodies 106and 106′ engage with the foot 114. The penetrator tip 108 and anteriorpenetrator tip 108′ of the elongate bodies 106 and 106′ engage withcuffs 110 and 110′ of the foot 114. The cuffs 110 and 110′ include alink 112 that connects the cuffs 110 and 110′ to one another. It shouldbe noted that the cuffs 110 and 110′ facilitate connection of thepenetrator tip 108 with the anterior penetrator tip 108′ such that thepenetrator tip 108 and the anterior penetrator tip 108′ are coupled toone another via the link 112.

FIGS. 16A and 16B show the suture bight in the pre-deployed state (FIG.16A) and the deployed state (FIG. 16B). The suture 102 is arranged toprovide the pre-tied knot 104 that automatically travels down from theshaft of the device where it is stored prior to delivery to the tissuewall. The loop 104 of suture 102 serves to pull the knot 104 down therail portion 140 of the suture during deployment. It should be notedthat it would be desirable to be able to distinguish the ends 140 and150 of the suture 102 during deployment so that the correct end ispulled by the operator to advance the knot. Should the non-rail end bepulled, the knot may be prematurely tightened before it is advance toits deployed position at the wall of the vessel.

The ends of the suture may be distinguished from each other by changingthe color of one end (e.g. with dye), providing an attachment on one end(e.g. shrink wrap tubing, a bead, etc.) or with the suture itself (e.g.tying a knot in one end).

FIG. 15C shows the penetrator tips fully deployed into and engaged withthe cuffs 110. FIG. 15D shows the penetrators being retracted after thetips have engaged the cuffs 110. On the anterior side 122, thepenetrator 106′ is pulling the anterior cuff 110 distally. On theposterior side 124, the penetrator tip 108 has been disengaged from thepenetrator 106, via a mechanism described below. As shown in FIG. 15D,the link 112 is now coupled to one end of the suture via posterior cuff110. Suture 102 is also shown exiting the posterior penetrator shank viaan opening in the side of the penetrator shank.

Referring to FIG. 15E, after deployment of the foot 114, the suture 102moves as indicated by directional arrows X₁. As the suture 102 moves, asuture loop 103 also moves in a direction indicated by directional arrowX₂ towards the foot 114 and the incision (not shown). The suture 102moves through the foot 114 and through an opening distal to the foot 114that defines a suture-bearing surface 111. The suture-bearing surface111 is disposed at a distal end of the suturing device 100 separate fromthe foot 114, in this embodiment. The suture bearing surface 111 bearsforces placed on the suture 102 during suturing. As such, thesuture-bearing surface 111 minimizes forces placed on an incision duringincision tensioning, thereby minimizing the possibility of damagingtissue immediately surrounding the incision. In this embodiment, thesuture bearing 111 is a slot disposed at a distal end of the suturingdevice 100, which includes a passage for the suture 102 during incisionsuturing as shown with reference to the Figure.

As the suture loop 103 and the suture 102 move, the pre-tied suture knot104 also moves in the same direction as the suture loop 103 towards thefoot 114 and the incision. The suture loop 103 continues to move thepre-tied suture knot 104 towards the incision until the suture 102 andthe pre-tied suture knot 104 suture the incision formed in the arterialwall. It should be noted that a suture trimmer might be used to assistthe delivery of the knot 104 to an arteriotomy. The suture trimmer maybe any device suitable for pushing the knot towards the arteriotomy andtrimming suture immediately adjacent the knot 104 once the knot istightened.

Now making reference to FIG. 15F, the suturing device 100 delivers thepre-tied suture knot 104 to the incision and the foot 114 is returned toits non-deployed position. The penetrators (not shown) have beenretracted, the link has been fully retracted through the knot, and theknot has been advanced to the vicinity of the arterial wall. When thebody of the device is removed, a stitch can remain in place across theincision in the artery. It should be noted that embodiments of thedevice described herein place a stitch of suture in a longitudinalorientation with respect to the vessel so as to minimize transversevessel constriction and also to take advantage of the transverseorientation of the fibers of the vessel tissue.

FIGS. 16A and 16B show the suture bight in the pre-deployed state (FIG.16A) and the deployed state (FIG. 16B). The suture 102 can be arrangedto provide the pre-tied knot 104 that automatically travels down fromthe shaft of the device where it is stored prior to delivery to thetissue wall. The loop 104 of suture 102 serves to pull the knot 104 downthe rail portion 140 of the suture during deployment. It should be notedthat it would be desirable to distinguish the ends 140 and 150 of thesuture 102 during deployment so that the correct end is pulled by theoperator to advance the knot. Should the non-rail end be pulled, theknot may be prematurely tightened before it is advanced to its deployedposition at the wall of the vessel.

The ends may be distinguished from each other by changing the color ofone end (e.g. with dye), providing an attachment on one end (e.g. shrinkwrap tubing, a bead, etc.) or with the suture itself (e.g. tying a knotin on end).

FIG. 17A shows an enlarged detail of the posterior portion of the footof one embodiment of suturing device 300. In an accordance with anembodiment of the present invention, the elongate body 306 may be anytype of structure capable of penetrating the wall of a lumen, such as anartery, a blood vessel, or the like. In addition to the penetrationcapability, the elongate body 306 may be a hollow tube capable ofholding suture. Examples of such structures may include a hypodermicneedle or the like. A cross-sectional configuration of another structureis illustrated in FIG. 17E.

With reference to FIG. 17E, the elongated body 306 can be configured toreduce the frictional engagement or contact between the suture 302 (FIG.17A) and the elongated body 306. As illustrated, the elongated body 306can include an exterior surface 340, and an interior surface 342, theinterior surface 342 defining a lumen that can be similar to the lumenor interior surface described with respect to FIG. 7A. The illustratedinterior surface 342 can include at least two portions having differingdiameters; at least one raised portion 344 and at least one recessedportion 346, optionally a plurality of raised portions 344 and aplurality of recessed portions 346, optionally in an alternatingconfiguration, which extend longitudinally along the length of theelongated body 306. The combination of the raised portions 344 andrecessed portions 346 reduce the contact surface between the suture 302(FIG. 17A) and the elongated body 306 and thereby reduce the frictionalforces between the suture 302 and the elongated body 306 or the suturedrag when the suture is moved inside the elongated body 306. Theportions 344 and 346 are another example of a structure capable ofperforming the function of reducing frictional engagement between asuture and the structure which selectively receives and/or restrains thesuture. Accordingly, the discussion related to portions 86 and 88 ofFIG. 7A also apply to portions 344 and 346 of FIG. 17B.

As illustrated, the plurality of raised portions 344 define a firstinner diameter id₁, while the plurality of recessed portions 346 definea second inner diameter id₂. With an outside diameter (od₁) of theelongated body 306, id₁ can be about 0.030 inches, while id₂ can anydiameter between the od₁ and the id₁. In the illustrated configuration,the id₂ can be between about 0.040 inches and about 0.030 inches. Itwill be understood by those skilled in the art that various otherconfigurations are possible. For example, although the raised portions344 and the recessed portions 346 are generally uniformly distributed onthe interior surface 346 irregular distribution of the portions 344 and346 is possible. Further, although the portions 344 and 346 aregenerally depicted as being uniform in size, shape, or generalconfiguration, non-uniform size, shape, or configuration of portions 344and 346 possible.

Returning to FIG. 17A, the suturing device 300 stores the elongate body306 within its shaft (not shown). As previously described with referenceto FIGS. 2A through 2C, a user deploys a handle (not shown) of thesuturing device 300 thereby deploying the elongate body 306 and thepenetrator tip 308. During deployment, the elongate body 306 and thepenetrator tip 308 penetrate the lumen wall W immediately surroundingthe incision 305 and enter the lumen 307 of a patient, as shown withreference the following FIG. 17B.

Once the penetrator tip 308 engages with the cuff 310, the elongate body306 and the penetrator tip 308, along with the cuff 310, proceed throughthe foot 314 and into the lumen 307. As may be seen with reference toFIG. 17B, the cuff 310 is pushed through the foot 314, such that thecuff 310 is pushed out of a pocket 316 and through the foot 314 into thelumen 307. Once the cuff 310 and the elongate body 306 enter the lumen307, the penetrator tip 308 detaches from the elongate body 306 via apush mandrel 315 as shown with reference to FIG. 17C.

FIG. 17C illustrates the detachment of the penetrator tip 308 from theelongate body 306 in accordance with one embodiment of the presentinvention. Upon engagement of the penetrator tip 308 with the cuff 310,the push mandrel 315 is further advanced such that it contacts aproximal surface 308 b of the penetrator tip 308, and further stilluntil the penetrator tip 308 detaches from the elongate body 306. Upondetachment of the penetrator tip 308 from the elongate body 306, thepush mandrel 315 and the elongate body 306 retract from the foot 314, asshown with reference to FIG. 17D.

As shown in FIG. 17D, after the penetrator tip 308 detaches from theelongate body 306, the elongate body 306 retracts from the penetratortip 308 and cuff 310. Meanwhile, on the anterior side of the device (notshown in FIG. 17D), the elongate body 306′ also includes the needle tip308′ which engages with the cuff 310′ as previously described withreference to FIG. 15C. The needle tip 308′ does not disengage from theelongate body 306′ upon engagement with the cuff 310′. Therefore, duringretraction of the elongate body 306′ from within the lumen 307, theneedle tip 308′ also retracts from the lumen 307 through the penetration309′. As the needle tip 308′ retracts through the penetration 309′, theelongate body 306′ also retracts the cuff 310′. As previously described,the cuff 310′ couples with the cuff 310 via the link 312. Duringretraction of the cuff 310′ through the penetration 309′, the cuff 310and the suture 302 also retract through the penetration 309′, therebydrawing the suture 302 through the penetration 309′. It should be notedthat the foot 314 may provide suture bearing surface for the suture 302during operation of the suturing device 300, as shown with reference toFIG. 18A.

FIG. 18A shows an embodiment of the present invention illustrating thepassage of the suture 302 through the lumen 307 and the passageways 309and 309′. As may be seen with reference to the Figure, the cuff pockets316 of the foot 314 provide a suture-bearing surface for the suture 302as the suture 302 is drawn through the passageways. The suture bearingsurfaces of the foot 314 minimize the possibility of the suture 302damaging tissue surrounding the incision 305.

In another embodiment shown in FIG. 18B, the suturing device 300 alsoprovides a suture bearing surface for the suture 302. During retractionof the elongate bodies 306 and 306′ from the lumen 307, the suture 302retracts through the foot suture bearing surfaces 314 a and thesuture-bearing surface 311 formed distally of the foot. The distalsuture bearing surface 311 and the foot suture bearing surfaces 314 aguide the suture 302 in order to minimize the possibility of the suture302 damaging the patient during retraction of the elongate bodies 306and 306′ from the lumen 307. In this embodiment, suture-bearing surface311 is a slot defined in the body of the device distal of the foot. Theslot includes a passage for the link and suture, and an edge 311 a. Itis contemplated that the edge 311 a may contact the edge of the incisionin the artery and become caught on the adventitia of the blood vessel.Various devices may be provided, such as flaps, o-rings, etc., thatprovide a smoother transition over the slot and edge 311 a as the deviceis inserted through the incision. Further, the slot, the elongated body,and/or any of the suture bearing surfaces can include friction reducingstructures to aid with passage of the suture along the suture path.

FIGS. 19A and 19B illustrate an alternative embodiment of the presentinvention for releasing the cuff 310 from the foot 314. In thisembodiment, the foot 314 includes link passageway 313 through which thelink 312 passes. After the elongate body 306 engages the penetrator tip308 with the cuff 310, the elongate body 306, during refraction from thefoot 314, removes the cuff 310 and the penetrator tip 308 from the foot314. The force holding the penetrator tip 308 on the elongate body 306overcomes the force holding the cuff 310 in the cuff pocket 316. Oncethe cuff 310 clears the foot 314 and attains the orientation shown withreference to FIG. 19B, the previously described push mandrel (not shown)detaches the penetrator tip 308 from the elongate body 306. Upondetachment of the penetrator tip 308 from the elongate body 306, thelink 312, along with the cuff 310 and the penetrator tip 308, retractsthrough the passageway 313 via the link 312 and the elongate body 306′.In an alternate embodiment, the cuff 310 and penetrator tip 308 may bepulled off the elongated body 306 by tension in the link 312.

In yet another alternate embodiment shown in FIGS. 20A through 20C, thecuff 310 and penetrator tip 308 may be detached from the elongate body306 before being removed from the cuff pocket 316. In this embodiment,after the elongate body 306 and the penetrator tip 308 engage with thecuff 310, the push mandrel 315 detaches the penetrator tip 308 from theelongate body 306, leaving it in the cuff pocket 316 to be removed bytension in the link 312, as shown in FIG. 20C.

It should be noted that other methods might be used to detach thepenetrator tip 308 from the elongate body 306. These methods include,but are not limited to, detachment through friction or tension. Makingreference to FIG. 20B, in an embodiment where friction between the cuffpocket 316 and the cuff causes detachment of the penetrator tip 308 fromthe elongate body 306, a surface 308 c of the penetrator tip 308frictionally engages with a cuff surface 316 a of the cuff pocket 316.During retraction of the elongate body 306 from the foot 314, thefrictional engagement between the cuff surface 316 a and the penetratortip surface 308 c causes detachment of the penetrator tip 308 from theelongate body 306. In an embodiment where link tension causes detachmentof the penetrator tip 308 from the elongate body 306, the link 312 istensioned such that the link 312 is taut between the cuffs 310 and 310′.As such, the tension of the link 312 prevents movement of the cuff 310out of the foot 314 along with the elongate body 306 during retractionof the elongate body 306 from the foot 314, thereby causing detachmentof the penetrator tip 308 from the cuff 310.

After detachment, during retraction of the elongate body 306 and theelongate body 306′ (not shown), the link 312 may draw the cuff 310 andthe penetrator tip 308 from the cuff pocket 316. As discussed earlier,the cuff 310′ engages with the elongate body 306′ and pulls the cuff 310via the link 312 as the elongate body 306′ retracts from the lumen 307.As such, retracting the link 312 pulls on the cuff 310, thereby pullingthe cuff 310 from the cuff pocket 316 and through the lumen 307 alongwith the suture 302, as shown with respect to FIG. 20C.

FIG. 21A shows the pre-tied suture knot 304 disposed about a peripheryof a knot tube 301. In this embodiment, the knot tube 301 includes ahollow center 301 a configured to allow passage of an elongate body (notshown) as the suturing device 300 sutures the incision. However, itshould be noted that in an alternative embodiment of the presentinvention, the elongate body (not shown) might also store the suture302. In the alternative embodiment, the suture 302 and the pre-tiedsuture knot 304 are disposed about a periphery of the elongate bodywhere the pre-tied suture knot 304 may reside within a pocket (notshown) of the elongate body.

An example of one body capable of storing the suture 302 is illustratedin FIG. 21B, and identified by reference numeral 301′. As shown, thesuture storage tube 301′ can include an exterior surface 340′, and aninterior surface 342′, the interior surface 342′ defining a lumen 301a′. The lumen 301 a′ can be configured to reduce the frictionalengagement or contact between the suture3 and the suture storage tube301′.

The illustrated interior surface 342′ can include at least two portionshaving differing diameters; at least one raised portion 344′ and atleast one recessed portion 346′, optionally a plurality of raisedportions 344′ and a plurality of recessed portions 346′, optionally inan alternating configuration, which extend longitudinally along thelength of the elongated body 306′. The combination of the raisedportions 344′ and recessed portions 346′ reduce the contact surfacebetween the suture 302 (FIG. 21B) and the elongated body 306′ andthereby reduce the frictional forces between the suture 302 and theelongated body 306′ or the suture drag when the suture is moved insidethe elongated body 306′. The portions 344′ and 346′ are another exampleof a structure capable of performing the function of reducing frictionalengagement between a suture and the structure which selectively receivesand/or restrains the suture. Accordingly, the discussion related toportions 86 and 88 of FIG. 7A also apply to portions 344′ and 346′ ofFIG. 21B.

As illustrated, the plurality of raised portions 344′ define a firstinner diameter id₁, while the plurality of recessed portions 346′ definea second inner diameter id₂. With an outside diameter (od₁) of thesuture storage tube 301′, id₁ can be about 0.030 inches, while id₂ canany diameter between the od₁ and the id₁. In the illustratedconfiguration, the id₂ can be between about 0.040 inches and about 0.030inches. It will be understood by those skilled in the art that variousother configurations are possible. For example, although the raisedportions 344′ and the recessed portions 346′ are generally uniformlydistributed on the interior surface 346′ irregular distribution of theportions 344′ and 346′ is possible. Further, although the portions 344′and 346′ are generally depicted as being uniform in size, shape, orgeneral configuration, non-uniform size, shape, or configuration ofportions 344′ and 346′ possible.

Embodiments of the suturing device of the invention may also includeadditional configurations for a foot, as shown with reference to FIGS.22A through 22C. In this embodiment, the suturing device 300 includes afoot 319 having cuff pockets 319 a and 319 b. The configuration of thecuff pockets 319 a and 319 b allow the foot 319 to hold the cuffs 310and 310′ during use of the suturing device 300. The foot pivots from afirst orientation shown with reference to FIG. 22A to a secondorientation shown with reference to FIG. 22B via a hinge 320 as shown inFIG. 22C.

FIG. 22C shows the hinge 320, which allows rotation of the foot 319 in adirection indicated by directional arrow Y. The hinge 320 may be anydevice capable of rotatably coupling the foot 319 to the suturing device300, such as pin assembly or the like. In addition to the hinge 320, thefoot 319 includes a connector 322 that couples the cuffs 310 and 310′with one another. The connector 322 also includes a flexible portion 322c (shown with respect to FIG. 22C) that allows flexing of the connector322 as the connector 322 resides within passage 317 of the foot 314. Theconnector also includes ends 322 a and 322 b that facilitate connectionwith the penetrator tip 308 and the needle tip 308′ of the elongatebodies 306′ and 306.

In an embodiment of the present invention where the suturing device 300employs the foot 319, during use of the suturing device 300, uponinsertion of the suturing device 300 within the lumen 307, a userdeploys the foot 319 as shown with reference to FIG. 22A. Upondeployment of the foot 319, the user deploys the elongate body 306 (notshown) that engages with the cuff 310 (not shown) as previouslydescribed. Once the penetrator tip 308 detaches from the elongate body306 via the push mandrel 315, or other means previously described, theuser rotates the foot 319 into the orientation shown with reference toFIG. 22B. Upon orientation of the foot 319 as shown with respect to FIG.22B, the user deploys the elongate body 306′ (not shown) which engageswith the cuff 310′ (not shown). After the elongate body 306′ engageswith the cuff 310′, the user retracts the elongate body 306′ along withthe cuffs 310 and 310′ and the suture 302 to suture an incision aspreviously described.

Another embodiment of the suturing device 300 includes feet 324 and 328as shown with reference to FIG. 23A. FIG. 23A illustrates an embodimentof the present invention in which the suturing device 300 includes thefeet 324 and 328. As may be seen with reference to FIG. 23B, the foot324 is hollow such that the foot 328 fits within the foot 324 duringboth insertion and retraction of the suturing device 300 within thelumen 307. The feet 324 and 328 also include cuff pockets 324 a and 328a and cam surfaces 324 b and 328 b. The configuration of the cuffpockets 324 a and 328 a allow placement of the cuffs 310 and 310′ withinthe feet 324 and 328 during use of the suturing device 300; allowingengagement of the elongate bodies 306 and 306′ during suturing. The camsurfaces 324 a and 328 a contact cam surfaces 326 a in order to deploythe feet 324 and 328. Once the feet 324 and 328 deploy, the suturingdevice 300 attains the configuration shown with reference to FIG. 23C.

During use of a suturing device implementing the feet 324 and 328, auser inserts the suturing device into an incision as the foot 328resides within the foot 324. Upon insertion of the suturing devicewithin the incision, the user deploys the feet 324 and 328 by moving thefeet 324 and 328 towards the cam surfaces 326 a, in order to deploy thefeet 324 and 328, as previously described. After deployment of the feet324 and 328 within a lumen, the user deploys the elongate bodies 306 and306′ whereby the penetrator tip 308 and needle tip 308′ engage with thecuffs 310 and 310′ residing within the cuff pockets 324 a and 328 a.Upon engagement with the cuffs 310 and 310′ the user retracts theelongate bodies 306 and 306′ and sutures the incision.

In addition to the alternative configurations for the foot of thesuturing device 300, the suturing device 300 may also includealternative cuff configurations that allow engagement of the elongatebodies 306 and 306′ with the link 312. An example of such an alternativeconfiguration is shown with respect to FIG. 24A. FIG. 24A illustrates aperspective view of an alternative embodiment of the penetrator tip 330.In this embodiment, a penetrator tip 330 includes mating surfaces 330 awhich engage with the previously described cuff tabs 310 a of the cuff310 when the penetrator tip 330 engages with the cuff 310, as shown withreference to FIG. 24B. As such, a user detaches the elongate body 306from the penetrator tip 330 with the push mandrel 315 after engagementof the penetrator tip windows 330 a with the cuff tabs 310, as discussedwith reference to the penetrator tip 308 and the cuff 310. The matingsurfaces 330 a may be cut-outs, such as windows, formed within thepenetrator tip 330. The elongate bodies 306 and 306′ may also engagewith the link 312.

FIG. 25A shows an alternative method of coupling the elongate bodies 306and 306′ with the link 312. In this embodiment, the elongate body 306′includes a loop 332 (shown in FIG. 25B) which engages with the link 312as the elongate body 306′ enters the foot 314. In this embodiment, thelink 312 is constructed of a resilient material capable of flexing inresponse to the loop 332 contacting the link 312, such as polypropyleneor any other material having spring-like characteristics. The elongatebody 306′ moves in a downward direction as indicated by directionalarrow A until the loop 332 comes into contact with an end 312 a of thelink 312. When the loop 332 contacts the end 312 a, the loop 332 movesthe end 312 a in a direction F₁ indicated by directional arrow F₁. Thecatch 332 continues to move the end 312 a of the link 312 in thedirection F₁ until the loop 332 contacts the end 312 a, as shown withreference to FIG. 25B.

Referring to FIGS. 25A-C, the link 312 is constructed of a materialhaving spring like properties. Therefore, when the loop 332 a comes intocontact with the end 312 a, the resilient properties of the link 312move the end 312 a in a direction F₂, as indicated by directional arrowF₂ in FIG. 25A. The end 312 a moves in the direction F₂ such that theend 312 a moves into the loop 332 a, as shown with reference to FIG.25B. Once the end 312 a moves into the loop 332 a, a user retracts theloop 332 along with the end 312 a and the link 312 in a direction B asindicated by directional arrow B of FIG. 25C. As the loop 332 a and thecatch 332 move in the direction B, the loop 332 a clamps the link 312against a surface 306′a of the elongate body 306′. Thus, duringretraction of the suturing device 300 from the foot 314, the link 312remains engaged with the elongate body 306′, as shown with reference toFIG. 25C. As the elongate body 306′ and the catch 332 retract from thefoot 314, the catch 332 pulls the link 312 through the foot 314, also asshown with reference to FIG. 25C. While the catch 332 pulls the link312, the cuff 310 (not shown) and the suture 302 (not shown) movethrough the foot 314 in order to enable suturing of an incision.

In another embodiment, the suturing device 300 may also employ a clipand ring assembly 338 which couples the elongate bodies 306 and 306′with the link 312, as shown with reference to FIG. 26A. FIG. 26Aillustrates a schematic view of the clip and ring assembly 338 forcoupling the elongate bodies 306 and 306′ with the link 312 inaccordance with an embodiment of the present invention. The elongatebodies 306 and 306′ include a clip 336 in place of the penetrator tip308 and the needle tip 308′ where the clip 336 has a configuration asshown with reference to the Figure. The clips 336 include flexible arms336 a and a passageway 336 b.

The clip and ring assembly 338 also includes a ring 334 that engageswith the clip 336. The link 312 couples with the ring 334 using anysuitable technique, such as tying or the like. The ring 334 has acircular configuration as shown with respect to FIG. 26B such that asthe elongate bodies 306 and 306′ engage with the foot 314, the clip 336couples with the ring 334. As the clips 336 engage with the ring 334,the flexible arms 336 a flex in a direction indicated by directionalarrows Y and Z thereby increasing a width W_(i) of the passageway 336 bin order to allow passage of the ring 334 through the clip 336 as shownwith regards to FIG. 28C.

Referring to FIG. 26D, there is shown a top view of the foot 314 wherethe foot 314 includes cuff pockets 314 b-1 and 314 b-2. The cuff pocket314 b-1 holds the ring 334 prior to engagement with the clip 336. Thecuff pocket 314 b-2 is configured such that as the elongate bodies 306and 306′ enter the foot 314, the clips 336 enter the cuff pocket 314 b-2and engage with the ring 334 as shown with reference to the Figure. Oncethe clip 336 engages with the ring 334, the clip 336 coupled with theelongate body 306 detaches from the clip 336 while the elongate body306′ remains engaged with the clip 336. During retraction of theelongate bodies 306 and 306′ from the foot 314, the elongate body 306′pulls the link 312 and the suture 302 through the foot 314 in order tosuture an incision.

FIG. 27 shows an embodiment of a cuff 410 and link 412 assembly that maybe provide with the various embodiments of the present invention. Cuff411 has a penetrator tip receiving end 434 and a tapered end 432. Link412 has two ends 442 (only one shown in FIG. 27). An example of one linkmaterial is expanded Polytetrafluoroethylene (ePTFE). PTFE is commonlyreferred to as Teflon. ePTFE is particularly suited for use as the linkmaterial in the vessel closure devices described herein because of itslow friction, high strength properties.

To assemble the link and cuff assembly, a length of link material isfirst threaded through the cuff. The end of the link material extendingfrom the penetrator tip receiving end 434 of the cuff 410 is then heatedso that it expands. The link is then pulled through the cuff 410 suchthat the expanded end portion 442 is seated in the interior tapered end432 of the cuff 410.

The various embodiments of the suturing device may include any of avariety of types of suture, such as braided or monofilament. The suturematerial may be absorbable or nonabsorbable and may be made ofpolyester, polypropylene, polyglycolic acid, nylon, silk or any of avariety of suture materials known in the art. Suture material coatedwith antibiotics or other antimicrobial agents may also be provided withthe suturing devices of the present invention.

An exemplary suture material is TEVDEK II®, a braided polyester suturematerial that is impregnated with PTFE and manufactured by GenzymeBiosurgery of Cambridge, Mass. An exemplary monofilament suture materialis DEKLENE II®, a polypropylene suture material also manufactured byGenzyme Biosurgery. Another exemplary monofilament suture material isnylon monofilament, also manufactured by Genzyme Biosurgery. Whilebraided polyester and monofilament polypropylene or nylon are suitablesuture materials that may be used with the devices of the presentinvention, monofilament suture materials may require post-manufacturingprocessing in order to form the pre-tied knot of the embodimentsdescribed with reference to FIGS. 11A through 11E and 14A through 21.

Monofilament suture material tends to be stiffer relative to braidedsuture material. As such, forming a bight of suture for the purpose ofproviding a pre-tied knot is more difficult with monofilament suturethan with the more flexible braided suture. The monofilament suturematerial can tend to straighten itself out after being looped to form abight 80 (shown in FIGS. 11Ai and 11Aii). Therefore, in order to providea bight of monofilament suture that is releasably disposed on the shaftof the device without unravelling, such as shown in FIGS. 11Ai and11Aii, FIG. 15A (pre-tied knot 104), and FIG. 21 (pre-tied knot 304),the loops forming the bight are heated to set the bight. The heating ofthe bight of monofilament suture to set the bight is performed after thesuture has undergone any manufacturing procedures that may includedrawing, annealling or any other procedure that employs heat tomanufacture the suture material.

A method of forming a pretied knot for a suturing device of the presentinvention includes providing a length of monofilament suture having afirst end, wrapping a portion of the length of monofilament suturearound a mandrel to form a looped configuration spaced from the firstend, and heating the wrapped portion to a temperature below the meltingpoint of the monofilament suture such that upon removal of the mandrel,the wrapped portion remains in the looped configuration.

The bight of the suture includes at least one loop. The heating of theat least one loop is performed to set the bight in the loopedconfiguration. The temperature is kept below the melting temperature ofthe suture material, yet is selected to cause the suture to remain inthe formed looped configuration after the bight is removed from theheat. The temperature is selected so as not to adversely affectproperties such as strength of the suture.

In one exemplary heating process, a length of size 3/0 polypropylenesuture is looped around a mandrel to form a bight which is heated at atemperature between about 240° F. to about 260° F., or nominally about250° F., for about 3 to about 5 seconds. The heat is provided by ablowing heat source such as a heat gun that provides an air flow at arate of about 10 to about 30 standard cubic feet per hour (scfh), ornominally about 20 scfh. The heating of the formed bight may beaccomplished in an oven that is heated to about 200° F. to about 280° F.When the bight is formed using an oven, the amount time that the bightis held in the heat of the oven is approximately 1 minute to about 15minutes. The specific heating temperatures and times may be selected asappropriate for different suture sizes or types, or different types ofbight configurations.

In another embodiment, a monofilament nylon suture material may beprovided to form a pre-tied knot in a suturing device of the presentinvention. The temperature at which a bight formed with size 3/0 nylonsuture is heated to set the bight is about 190° F. to about 210° F., andnominally about ° F., for about 3 to about 5 minutes with a blowing heatsource such as a heat gun. In an oven, the temperature used at which thebight is set is about 190° F. to about 210° F., or nominally about 200°F. for about 1 minute to about 15 minutes.

FIG. 28 shows a bight 580 of monofilament suture wrapped around amandrel 589 in preparation for heating the loops of the bight to set thebight. The mandrel may be a polyimide shaft or tube having a diameter ofabout 0.65 mm, for example. In the example shown in FIG. 28, the sutureis size 3/0 and is wrapped to form a looped configuration which definesa clinch knot. To wrap the suture as shown in FIG. 28, a length ofsuture is held against the mandrel with a first end 576 oriented acrossthe mandrel. The second end of the length of suture is wrapped fivetimes around the mandrel. The second end is then wrapped over the firstend to form loop 590 transverse to the first five loops. The second endis then looped behind the mandrel and wrapped over the mandrel in theopposite direction from the first five loops. The second end is thenrouted through loop 590 to form the pre-arranged or pre-tied knot.

The present invention offers surgeons an automated method for deliveringa pre-tied knot to an incision formed in a lumen. The present inventionminimizes the problems associated with a surgeon manually delivering aknot to an incision site. Thus, the present invention reduces the timerequired to accurately and precisely place a suture knot in closeproximity to an incision formed in a lumen, thereby decreasing both theoverall time a patient spends in procedure and the costs associated withthe procedure.

While illustrative embodiments of the invention are disclosed herein, itwill be appreciated that numerous modifications and other embodimentsmay be devised by those skilled in the art. For example, the variousfeatures of each embodiment may be altered or combined to obtain thedesired device or method characteristics. Therefore, it will beunderstood that the appended claims are intended to cover all suchmodifications and embodiments that come within the spirit and scope ofthe present invention.

What is claimed is:
 1. A method for suturing an opening in tissue, themethod comprising: inserting a distal end of a device through anopening; articulating an elongate foot of the device so that first andsecond ends of the foot extend laterally with the opening alignedtherebetween; supporting a link by the first and second ends of thefoot; forming a first penetrator path from the device through the tissueand to the first end of the foot; forming a second penetrator path fromthe device though the tissue and to the second end of the foot;advancing a first end of a flexible filament along the first penetratorpath and along at least a portion of at least one friction reducingstructure to attach to the link, the at least one friction reducingstructure comprising at least one recessed portion and at least oneraised portion; advancing an elongate body along the second penetratorpath to attach to the link; coupling the first end of the flexiblefilament and the elongate body via the link; retracting the elongatebody along the second penetrator path, thereby drawing the link and thefirst end of the flexible filament through the second penetrator path toform a loop across the opening.
 2. The method of claim 1, wherein the atleast one recessed portion is in an interior surface of the lumen. 3.The method of claim 1, wherein the at least one recessed portion and theat least one raised portion are on an interior surface of the lumen. 4.The method of claim 1, wherein the at least one recessed portion and theat least one raised portion are disposed on an interior surface of thelumen in an alternating fashion.
 5. The method of claim 1, furthercomprising a suture bearing surface disposed near the distal end of theshaft.
 6. The method of claim 1, wherein the flexible filament is asuture.
 7. The method of claim 6, wherein the suture is a monofilamentsuture.
 8. The method of claim 1, wherein a first length of flexiblefilament extends between a first fitting at the first end of the foot toa second fitting at the second end of the foot, and wherein a secondlength of flexible filament extends from a third fitting at the firstend of the foot to a fourth fitting at the second end of the foot, andwherein each fitting securingly engages an associated needle to drawends of the first and second length of flexible filament through thevessel wall and form a plurality of loops across the puncture.
 9. Themethod of claim 1, wherein the plurality of raised portions arehelically formed on the interior surface of the lumen.
 10. The method ofclaim 1, wherein the plurality of raised portions are formed at anangular orientation relative to a longitudinal axis of the lumen. 11.The method of claim 2, wherein the at least one recessed portion and theat least one raised portion are on an interior surface of the lumen. 12.The method of claim 11, wherein the at least one recessed portion andthe at least one raised portion are disposed on an interior surface ofthe lumen in an alternating fashion.
 13. The method of claim 12, furthercomprising a suture bearing surface disposed near the distal end of theshaft.
 14. The method of claim 13, wherein the flexible filament is asuture.
 15. The method of claim 14, wherein the suture is a monofilamentsuture.
 16. The method of claim 15, wherein a first length of flexiblefilament extends between a first fitting at the first end of the foot toa second fitting at the second end of the foot, and wherein a secondlength of flexible filament extends from a third fitting at the firstend of the foot to a fourth fitting at the second end of the foot, andwherein each fitting securingly engages an associated needle to drawends of the first and second length of flexible filament through thevessel wall and form a plurality of loops across the puncture.
 17. Themethod of claim 16, wherein the plurality of raised portions arehelically formed on the interior surface of the lumen.
 18. The method ofclaim 17, wherein the plurality of raised portions are formed at anangular orientation relative to a longitudinal axis of the lumen.